A person expert in analyzing and breaking codes and cyphers.(noun)
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Use "cryptanalyst" in a sentence
"Fellow cryptanalyst Thomas Dyer was one of many who believed that Rochefort was targeted for showing up his detractors."
"Rochefort was a 42-year-old cryptanalyst and a man not given to hyperbole."
"First, you didn't paste the part of my quote where I explained that a cryptanalyst working in conjunction with a mathematician may be able to discover that the pattern is indeed specified without anyone telling them."